Anthropometric measurements in infants conceived by assisted reproductive techniques versus spontaneous conception

Objective: To compare body length and head circumference at birth of neonates conceived after in vitro fertilization/intracytoplasmic injection (IVF/ICSI), ovarian stimulation alone (OSa) or by natural conception (NC). Methods: A retrospective, cohort study of all singleton neonates conceived after fertility treatment and born at 38-40 gestational weeks in 2011 in a tertiary, university-affiliated hospital. Pregnancy, delivery and neonatal data were obtained from the medical records. NC singleton neonates born at 38-40 weeks were selected to serve as controls. Results: The sample included 81 IVF/ICSI neonates, 102 OSa neonates and 91 neonates after NC. Mean gestational age (GA) was 38.8 weeks. Gravidity and parity were significantly higher in the NC group. Mean neonatal length was 50.0 +/- 2.1 cm in the IVF/ICSI group, 49.7 +/- 2.6 cm in the OSa group and 50.3 +/- 2 cm in the NC group (p = 0.123). Corresponding mean head circumference was 34.4 +/- 1.5, 34.2 +/- 1.8 and 34.5 +/- 1.2 cm (p = 0.287). Neither of these parameters was significantly different even after adjustment for GA at delivery and sex. Conclusions: Our study showed no significant difference in body length or head circumference at birth related to the mode of conception. Previously reported differences in anthropometric parameters in childhood may be related to other factors.